Characterisation of CaO-ZrO2-SiO2 glasses by MAS-NMR and molecular dynamics

In this work a wide series of compositions, belonging to the CZS ternary system, are analysed. The linear expansion coefficient of the glass materials is experimentally determined and the results are interpreted by comparison with the structural information derived by molecular dynamics simulations and by Si-29-MAS-NMR. The analysis of the alpha values indicate that, while the ZrO2 acts as network former in these glasses, CaO shows network modifier behaviour producing a decrease of the network complexity. The characterisation of the short and intermediate range structure, obtained by the MD and Si-29-MAS-NMR analysis, allows one to define the relationships between the structure modifications induced by the different oxides, and the physical properties of the glasses experimentally observed.